Skip to main content

Your Apple Watch’s SpO2 sensor might be a lot better than you thought

The Apple Watch’s SpO2 sensor that allows wearers to measure their blood oxygen levels was impressive when it first debuted, but it may be even more accurate than initially marketed.

According to a recent study, the Apple Watch’s blood oxygen reader is comparable to medical-grade pulse oximeters. Although Apple Watches shouldn’t be used in lieu of official medical devices, it’s nice to know that the readings they’re displaying are accurate enough to be reliable.

The case back differences between the Apple Watch SE 2 and Apple Watch Series 8.
Apple Watch SE 2 (left) and Apple Watch Series 8 (right) Andy Boxall/Digital Trends

First reported by 9to5Mac, the study was published this month in the Digital Health journal and sought to compare a “commercially available smartwatch” to a medical-grade pulse oximeter. The watch the study used was the Apple Watch Series 6, the first of Apple’s smartwatches to include an SpO2 sensor, which is over two years old at this point.

Recommended Videos

The results of the study showed that the Apple Watch “can reliably detect states of reduced blood oxygen saturation with SpO2 below 90% when compared to a medical-grade pulse oximeter.” To come to that conclusion, the study used 24 healthy participants, each one wearing an Apple Watch Series 6 on their wrist and clamped a Masimo Radical-7, a common pulse oximeter, on the middle finger of the same hand. The participants then did various breathing exercises to manipulate their blood oxygen levels to see how the Apple Watch performed when compared to the Masimo Radical-7. By the end of the tests, there were 642 blood oxygen readings to compare.

To reiterate: If you’re looking for a fully accurate blood oxygen level reading, it’s still best to use a proper medical device. But the results of the study show that Apple’s wearable tech is certainly moving in the proper direction for providing accurate medical information. In addition to the SpO2 sensor, Apple Watches provide alerts for irregular heartbeat rhythms that may suggest atrial fibrillation, medication intake reminders, and sleep tracking.

While Apple doesn’t claim that any of its devices can be used as concrete medical readers, the features that have been added to Apple Watches, in particular, are extraordinarily useful for those looking to monitor their bodily functions and have informed conversations with healthcare providers should they discover anything noteworthy.

Peter Hunt Szpytek
Former Digital Trends Contributor
A podcast host and journalist, Peter covers mobile news with Digital Trends and gaming news, reviews, and guides for sites…
Why you shouldn’t buy a new Apple Watch right now
The curved screen on the Apple Watch Series 9.

It has been over six months since the Apple Watch Series 9 and Apple Watch Ultra 2 launched, and they are still considered two of the best smartwatches on the market. However, there are two significant reasons why you might not want to purchase either of these models.

Those reasons are the Apple Watch Series 8 and the first-generation Apple Watch Ultra. That's right — buying a 2022 Apple Watch over the newer models might be a better choice for you.
Why now's a great time to buy an old Apple Watch
The Apple Watch Series 9 (top) and Apple Watch Series 8 Andy Boxall / Digital Trends

Read more
8 watches you should buy instead of an Apple Watch
A person wearing the Apple Watch Series 9.

The Apple Watch Series 9 is the best smartwatch you can buy, regardless of the fact you can only use it with an iPhone. It's also great that it comes in three flavors — the Series 9, along with the Apple Watch SE 2, and the Apple Watch Ultra 2 — to suit many more people and pockets than you may first think. However, perhaps you want something a little different on your wrist or even a weekend alternative when you don’t feel like wearing a touchscreen watch.

That’s where this list should help you out, as we’ve gathered eight watches to buy instead of the Apple Watch. Notice I said “watches,” and not just smartwatches, as some non-connected wristwear has been included. Our choices cover the entire Apple Watch range in terms of price, even going above and below, to give you some real inspiration about a watch to buy instead of — or as well as — the superb Apple Watch.
Casio G-Shock GPR-H1000 Rangeman
Casio G-Shock Rangeman Andy Boxall / Digital Trends

Read more
This $130 iPhone charger is better than Apple’s official one
Twelve South ButterFly 2-in-1 MagSafe Charger held in hand.

When you travel, less is more. This is especially true for your electronic devices, which can quickly become a mess due to all their various cables and chargers. That’s why having combo products works in your favor for these scenarios.

Twelve South has recently launched a new MagSafe charger for your iPhone, Apple Watch, and even AirPods that is super compact without compromising on charging speed. It’s the ButterFly 2-in-1 MagSafe Charger, and it’s a perfect accessory for your travel kit or bag.

Read more